constify to_disconnect

constify to_disconnect

This constifies an parameter of to_disconnect and updates
target_disconnect as well.

2014-06-16  Tom Tromey  <tromey@redhat.com>

	* target.h (struct target_ops) <to_disconnect>: Make parameter
	const.
	(target_disconnect): Update.
	* target.c (target_disconnect): Make "args" const.
	* target-delegates.c: Rebuild.
	* remote.c (remote_disconnect): Update.
	* record.h (record_disconnect): Update.
	* record.c (record_disconnect): Update.
	* inf-child.c (inf_child_disconnect): Update.